Known FM receiver headphones have unsatisfactory performance when used with low power FM transmitter products. Existing FM receiver headphone products are typically designed for urban and suburban use where the signal level of the desired signal is quite strong. In such an environment a proper receiver may be designed with good selectivity (i.e., the ability to reject unwanted adjacent channel signals) but not very good sensitivity due to the intermodulation problems it can cause, and the component cost of achieving increased sensitivity. The fact that reduced sensitivity is acceptable in these devices also allows a compromise in antenna implementation, while still yielding satisfactory results with strong signals.
As low power FM transmitter products are limited to very low output power by regulatory authorities, a low-noise receiver and optimum antenna are required to maximize the useful range of a receiver.
The foregoing discussion reflects the current state of the art of which the present inventor is aware. Reference to, and discussion of, this information is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above information discloses, teaches, suggests, shows, or otherwise renders obvious, either singly or when considered in combination, the invention described and claimed herein.